Regulators in the United Kingdom have approved Moderna’s new Omicron-specific COVID-19 vaccine for an upcoming nation-wide autumn booster program. The approval makes the UK the first region in the world to formally move forward with an improved variant-targeting vaccine.
Moderna’s new mRNA vaccine was approved by the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) as a booster shot for all adults aged over 18. The vaccine is bivalent, meaning it contains mRNA coding for two different SARS-CoV-2 antigens – the original strain’s spike protein and a spike for the BA.1 subtype of the Omicron variant.
“The first generation of COVID-19 vaccines being used in the UK continue to provide important protection against the disease and save lives,” said June Raine, chief executive of the MHRA. “What this bivalent vaccine gives us is a sharpened tool in our armory to help protect us against this disease as the virus continues to evolve.”
From September all adults in the UK will be offered a booster shot. This booster program is not limited to Moderna’s new bivalent vaccine, and will also include options for a shot of the original mRNA vaccine.
In June an advisory group to the World Health Organization (WHO) evaluated early clinical data from both Pfizer and Moderna regarding their Omicron BA.1 variant vaccines. Despite other Omicron variants subsequently becoming predominant around the world the advice was a BA.1 booster should be an effective way to broaden a person’s general immunity against emerging SARS-CoV-2 variants.
The US Food and Drug Administration (FDA), on the other hand, came to a different conclusion following an expansive meeting of its own advisory panel. The FDA indicated a BA.4/5 variant-specific booster would be preferable for a US booster program.
The FDA’s decision was based on observations of BA.5 becoming dominant in the US. However, because both Moderna and Pfizer had initially focused on development of a BA.1 vaccine, the FDA’s recommendation meant any updated vaccine booster program would face a delayed roll-out.
It is still unclear exactly when updated BA.5 boosters will be available. It is possible they could be accessible to Americans as soon as September or as late as November.
In the meantime, with the UK’s approval of Moderna’s BA.1 booster, several other regulatory bodies around the world are likely to follow with similar announcements, including the European Union and Canada. As the Northern Hemisphere moves towards its third pandemic winter it is anyone's guess as to what SARS-CoV-2 variant will ultimately dominate spread later in the year.
